Mobile electrical devices such as cellular phones often employ rechargeable batteries which, due to weight and size constraints, require frequent recharging. While many battery charger designs exist, they tend to be bulky and cumbersome. Yet because of the relatively short life of rechargeable batteries, the charger must be carried with the batteries for all but brief uses.
A typical and popular battery charger is exemplified in Weiss, et al., U.S. Pat. No. 5,059,885, assigned to Motorola, Inc. and incorporated by reference herein in its entirety. Weiss discloses a battery charger having a housing with two recesses for positioning and supporting batteries of different size or capacity. However, in order to support the batteries in their charging position, the battery charger housing must be relatively large and cumbersome. Moreover, available commercial embodiments of the apparatus disclosed in Weiss require an external power supply to power an internal battery charging circuit, thereby adding to the complexity and burden of using the available apparatus.
Accordingly, there is a need for a battery charger with reduced size to facilitate transportation and storage that is readily compatible with a variety of current supplies.